A global problem that is receiving a lot of attention is how to supply energy to the population of the world. As a proposed solution, many believe that it would be highly beneficial if the use of fossil fuels was decreased and replaced with renewable sources of energy. Accordingly, efforts have been made to harness natural kinetic resources to meet ever increasing electrical power generation needs. However, about 90% of U.S. electric production sill comes from nonrenewable sources.
A significant percentage of the efforts to use renewable sources of energy has been concentrated on wind powered systems. In the U.S., wind powered systems currently only account for about 10% of renewable electricity sources despite wind systems having increased in their prevalence by 35% from the period of April 2008 to April 2009, according to Energy Information Association (“EIA”) Reports. Conversely, while conventional hydroelectric systems account for about 77% of the U.S. renewable energy supply, they have fallen out of favor in the U.S. as more evidence is uncovered on the potential enormous environmental and geological impact created by such systems.
One of the principal reasons for the small percentage of wind powered generating systems is that they suffer from the obvious problem that wind energy is inherently intermittent. Wind power generating systems are also somewhat limited in terms of where they can be located and typically, need to be located in areas that are known to experience a significant amount of wind. This presumes that these high wind areas would be susceptible to construction of such wind power generating systems, which they frequently are not.
Common hydroelectric systems include submersible plants for producing electricity from ocean currents. Those plants are typically fastened to the sea bottom by wires and comprise turbines arranged to be driven by tidal water. However, the power generated from submersible plants needs to be increased without substantially increasing the energy gathering costs in order for this energy source to be commercially attractive.
Consequently, vast scientific and financial resources have been expended in pursuit of hydrokinetic turbines which can convert kinetic energy within a normal flow of a body of water into a useful amount of electrical energy at a reasonable cost. Despite these efforts, hydrokinetic turbines deployed in the normal flow of a body of water have nevertheless not been successfully developed to the point where they can deliver adequate amounts of electric power at a reasonable “per kilowatt hour” cost, with an acceptable level of reliability. This is complicated by the fact that hydrokinetic power systems are limited by the number of available locations for their installation and typically can only provide the desired results in rivers that are fast flowing and deep.
In addition to the limitations with hydrokinetic systems, the successful deployment of the individual hydrokinetic turbines is also inherently problematic. First, the rotation of a turbine about an axis in one direction generates an equal yet opposing counter-torque in the opposite direction. To counteract this counter-torque and maintain stability of the hydrokinetic turbine, a mounting apparatus such as a series of anchored support posts or columns are attached to the hydrokinetic turbine and then anchored to a stationary structure, such as the floor of a river, a bridge or some other immovable object. While this serves to stabilize the hydrokinetic turbine, it prevents ease of adjustment of the turbine location to a different point within the moving body of water where current flow is optimum. As the characteristics of the flowing body of water change due to an increased volume of water, freezing, etc., the point of optimum flow also changes. The lack of mobility of a deployed hydrokinetic turbine limits the adaptability of the turbine to such differing conditions and creates a corresponding decrease in the efficiency of the system.
Further, existing hydrokinetic turbines are relatively expensive. Conventional turbines, and specifically hydrokinetic turbines, have typically been constructed of steel or lightweight metal such as marine aluminum for a variety of reasons. First, constructing these of metal provides increased durability, particularly in harsh surroundings. Second, a fairly heavily weighted turbine housing, in conjunction with conventional anchoring mechanisms described above, provides the configuration best able to withstand and minimize the effects of counter-torque generated by rotation of the turbine blades and shaft. On the downside, the cost of manufacturing a hydrokinetic turbine from a metal material is extremely expensive.
Accordingly, there exists a need for a hydrokinetic turbine which overcomes the existing problems with hydrokinetic technology. More specifically, there exists a need for a hydrokinetic turbine which can be stabilized in a path of water flow without complex anchoring mechanisms. There is a further need for a hydrokinetic turbine which can be placed in a particular optimal position in a path of water flow, then easily maneuvered to a different position within the body of water in the event of a change of location of the optimal path of water flow. Finally, there is a need for a hydrokinetic turbine unit complying with the above-stated needs which is also economical to build and operate.